A Design Method for a Leaky-Wave System With Uniform Field Coverage and Broadside Radiation for a Vacuum-Tube Ultra-High-Speed Train

Abstract

The communication system for vacuum-tube ultrahigh-speed trains faces great challenges from unstable signal coverage and severe Doppler effects as a result of long running distances and ultrahigh speeds. This communication presents a possible solution for a communication system in a vacuum-tube high-speed train system that operates using a leaky waveguide. The design method for the leaky waveguide is demonstrated in detail. The developed leaky waveguide consists of periodic metal posts and longitudinal slots in a staggered arrangement, and it can achieve the properties of uniform field coverage and broadside radiation. Therefore, the performance of long-distance transmission with stable signal quality can be realized, and the Doppler effect in the scenario of ultrahigh-speed rail can be mitigated. Leaky waveguides with lengths of 5, 10, and 20 m are designed as verifications of the method. A 5 m leaky waveguide is fabricated and measured. The measured results are consistent with the simulated results, demonstrating that a uniform field distribution and broadside radiation can be achieved using the developed leaky waveguide.